How to get started with lexical selection rules

First approach

Choose your words

Before you start making lexical selection rules, you first want to choose a word in your source language (e.g. English) which has more than one translation in your target language (e.g. Spanish). For example

• argument → discusión
• argument → polémica
• argument → argumento

Think about context

The words around our word often help us decide how to translate it, for example, a verb might inform us of how to translate a noun, or a noun might inform us of how to translate an adjective.

If we say "to have an argument", then it probably means "discusión", whereas if we say "to accept the argument", then you probably want to translate it as "argumento".

Think about synonyms and antonyms

Once you have a rule, one way of making it more general is to think of synonyms and antonyms for the context words. For example, if you have the rule:

	<rule>
	  <match lemma="positive" tags="*"/>
	  <match lemma="charge" tags="n.*">
	    <select lemma="carga" tags="n.*"/>
	  </match>
	</rule>

You could quite easily think that the antonym of "positive" is "negative", and add that too:

	<rule>
          <or>
	    <match lemma="positive" tags="*"/>
	    <match lemma="negative" tags="*"/>
          </or>
	  <match lemma="charge" tags="n.*">
	    <select lemma="carga" tags="n.*"/>
	  </match>
	</rule>

Think about semantically related words

If you have the rule:

	<rule>
	  <match lemma="wind" tags="*"/>
	  <match lemma="power" tags="n.*">
	    <select lemma="energía" tags="n.*"/>
	  </match>
	</rule>

You might think that the translation of "power" as "energía" (instead of the default translation poder) can happen more times than only after "wind", for example, "solar power" energía solar, "wave power" energía olamotriz

And even thinking about these can bring you to other rules, for example "electrical power" is not energía eléctrica, it's potencia eléctrica.

Look at a concordance

A concordance (or "key word in context") is a set of sentences where they are centred on a single word (sometimes called the "key word"). To make a concordance you can use a concordancer (e.g. apertium-concord).

Here is an example from EuroParl:

   represent, to the President and to the Governor of Texas, Mr Bush, who has the power to order a stay
            We should do everything within our We should do everything within our power to force the
                      On the market, the balance of On the market, the balance of power between supply and
                  The scandalous concentration of The scandalous concentration of power in sectors of strategic 
  fact, retaining not only the The Commission is, in fact, retaining not only the power
        the balance of I therefore feel we must carefully consider the balance of power that we are in
  the sea's Having spent a lot of time at sea myself I am well aware of the sea's power and destructive force, 
  The Commission is following with interest the planned construction of a nuclear power plant in Akkuyu, Turkey
    siting, construction, commissioning, operation and decommissioning of nuclear power plants in Turkey rests
  a serious risk that some idiot will decide that the new geopolitical balance of power in the Caucasus calls
  in the development of that nuclear If we see in the development of that nuclear power
  build a nuclear If the conclusion is that Turkey is planning to build a nuclear power plant that does not
  none of the upheaval would have been caused had we not acted with parliamentary power to press for changes
     yet the police are being forced into a position where they will not have the power to resist the terrorist
   right to interfere in the formation of a government even though it has assumed power on the basis of
       unusual about what is happening in Austria: there has been a changeover of power following democratic 
          for this Intergovernmental Conference to score a hat trick; that of the power to act, democratic 
  course, we need to create the At the same time of course, we need to create the power to act in order
      The European Union must also have the The European Union must also have the power to act
      unconscious but undoubtedly rational initiatives dictated by the desire for power and pointing in the
                                                The discretional The discretional power of the State, which you 
  improve both the functioning of the internal market and the competitiveness and power to act of enterprises.
                    We must create forms of motive We must create forms of motive power which are not
                                        If we develop motive If we develop motive power of the kind I have
    up the IGC agenda beyond issues strictly related to redressing the balance of power between Member States,
     conflict with the Treaty and apportion to the institutions of the Union more power than that to which
  political respectability on right wing extremism and also giving them access to power - both of which
     a party which is openly pro-Nazi, racist and xenophobic has gained access to power in a European country.
                It turned its threatened loss of It turned its threatened loss of power into an "heroic
       we need to focus our attention is the possibility of nepotism and abuse of power within regional and local
    But the fact that we now fear abuse of But the fact that we now fear abuse of power
      have taken place on major strategic options which the Commission, under its power of initiative, launched,
   today, we do not have definite answers regarding the monitoring of the nuclear power stations in the eastern
        grow more distant will leave the way open for an oligarchy that will take power and leave control in
    to give all decision-making You are now proposing to give all decision-making power to
   If we are to ensure that we defeat the fear-mongers amongst us - those seeking power on the backs of
                    Will you do everything in your Will you do everything in your power to ensure that
                    Will you do everything in your Will you do everything in your power to ensure that
  substance and yet, at the same time, is asking for ever greater decision-making power to the detriment of
      in direct dialogue with the public, and not just with the élite or those in power whom we meet as
           of the text to be submitted to the Heads of State and Government, this power must be exercised with
   reach The fact that an openly extremist, racist and xenophobic party can reach power in a Member State
            It is good for us that we have the It is good for us that we have the power
                    A new government has come into A new government has come into power in Austria, comprising
   in recent weeks in helping to cope with the considerable difficulties with the power supply in Kosovo.
     given the beginning of such a True, we are now given the beginning of such a power in this new system.
     Convention, I would like to urge the Member States to do everything in their power to speedily ratify this
     advocates reorganising European and national institutions, strengthening the power of the state, increasing
                                                In this way, the In this way, the power of globalisation can be 
   party in This is occurring in my country, despite the government, the party in power being the only one
                          I do not understand why the I do not understand why the power centres of Europe
       have been a public affair and, as such, just like public transport and the power supply, a core task
   third period, the composition of the bodies which wield political and economic power needs to be changed.
  responsible undertook to implement specific measures and policies to change the power ratio.
     of women on committees who wield The number of women on committees who wield power and
      have been effective as far as the decision-making centres of the parties in power is concerned, the same
          Excluding women from the centres of Excluding women from the centres of power means, first, democratic
        to surrender positions of Men have never wished to surrender positions of power when
      for the same reasons of Inevitably, we should like, for the same reasons of power
     since been banned in all those countries in which fascism and racism came to power during and between the
  my colleagues in supporting and assisting fellow citizens in my country to gain power and access to
  simply, I would say that there are several ways in which to attain positions of power and I am particularly
  plan would be a benchmarking system to guarantee women' s full participation in power structures and decision 
    between the sexes, for distributing public offices and political and economic power fairly and evenly between
   instead of a redundancy notice. So too did the Danish Government which came to power in 1993.
   powerful European approach, where the fifteen Member States do not try to gain power but where the power
  to technology, but without any change to social structures, we need a debate on power and the distribution of
            Or have industrialisation, nuclear Or have industrialisation, nuclear power and biotechnology led to 
         Council must have as much clout as the ECOFIN Council and that political power must remain in the
   but we believe it can be more effectively enforced if Member States retain the power to establish their own
    everything in our We shall then be grateful if we have done everything in our power to prevent oil spills.
   to give the European Council the Any proposal to give the European Council the power of
                                                                        Such Such power must at all times be 
    President, rules make sense if their purpose is to protect people against the power of money, against health
    a great concentration of We do this because there is a great concentration of power at the centre of
   exercise far too much The EU organs and institutions can exercise far too much power to permit them that
  IGC should not simply be a kind of discussion of the division and management of power in an enlarged Union.
    hard on Bulgaria and to go far too far, and because safety standards at these power stations were said not
      that a recycling industry is developing which possesses such competence and power in terms of financial
  and of refuse collection and disposal than of, for example, generating combined power and heat.
                                                        It is in the It is in the power of the United Kingdom 
                                                Her strength and Her strength and power for evil purposes is 
  not be possible to conduct inquiries into corruption and the abuse of political power without fear of political
        based on the fairer distribution of wealth, an increase in the purchasing power of households and the
     were to improve the standard of living of workers, increase their purchasing power and guarantee safe jobs,
                                                    Therefore, the Therefore, the power that is given to the 
         at defining exactly the respective role of the executive and legislative power in the basic legislative
  confers a I submit that this is inappropriate, because it effectively confers a power on the Commission to
      lose In what way do the European Council and the European institutions lose power and the potential to
   of Amsterdam, I think it is important for us to bear in mind that transfers of power have taken place, and
      in Mr President-in-Office of the Council, you said that there is a party in power in Austria which has
   not think that it is rather difficult to accept that an economic and political power such as Europe, which
  to your questions about the nuclear Turning to your questions about the nuclear power stations in
  financing required for improving the degree of efficiency and safety of nuclear power stations in certain 
     have the Mr President, it is clear that the European Union does not have the power to intervene in the
  legislative work in open meetings, only parliaments do that, and as legislative power is divided between 
           these fears about Europe losing ground in Mexico against the exporting power of the United States.
      in the context of the development of a technology operated chiefly by a big power which, while teaching 
      has potential to transfer The information society has potential to transfer power from government
  to support the view that those in This is not to support the view that those in power can do as they

Try a parallel corpus

You can look at which contexts are used in one translation, but not another by looking at a parallel corpus.

$ paste europarl-v6.es-en.en europarl-v6.es-en.es | grep ' power .* potencia '
Since the Union as a whole is a world-class fishing '''power''' and one of the largest markets for fish produce, ...
Por ser la Unión en conjunto una '''potencia''' pesquera en el nivel mundial y uno de los mayores mercados de productos pesqueros, ...

See also

• Constraint-based lexical selection module‎