Page 279 - English - Teaching Academic Esl Writing

SUBORDINATE CLAUSES 265
• The future marker will is turned into would; and would have in negative with the meaning of did not... (e.g., He said that hewould studyforthetest[hedid],and Hesaidhewouldhavestudiedforthetest [he actually did not]).
•
Can turns into could in positive constructions, and could have in negative also with the meaning of did not... (e.g., Shetold methat she could help me, and She told me that she could have helped me).
• May becomes might (e.g., They mentioned that they might come).
• Should and might do not change (e.g., Wesaid that we should/might
go).
• Must becomes had to (e.g., They told us that we had togo).
Given that these rules mention only some of the most important tense and verb changes in noun clauses, it is not difficult to see how implementing them may become hairy indeed. However, the conventionalized uses of tenses in academic writing can be used to L2 writers' advantage because the range of tenses and aspects in written prose is far more limited than that in conversational discourse (or most ESL grammar books).
In academic writing, the large number of rules and specific verb conver- sions in noun clauses can be simplified to a great extent:
The verb tense in the main clause determines the tense in the noun clause. If the main clause is in the past, the noun clause verb can take the simple present or simple past tenses. The present tense is far eas- ier to use in both main and noun clauses than to change verbs to past-tense forms (no positive/negative worries) or replace the verbs altogether.
In a sentence such as, Researchers noted that it may/might bedifficult to tell the difference between depression and learned helplessness, the verb in the noun clause can be changed to the past tense or remain in the present tense, and both constructions can be perfectly usable, although their meanings differ slightly.
Another possibility for using tenses in noun clauses correctly is simpler still (see chap. 7):
Whenever possible, the simple present tense should be used in the main and the noun clauses, with the exception of case studies and historical or biographical contexts, which are specifically flagged for the past tense by means of past time adverb phrases (or other markers).
In the following two examples, the present tense and past tense in the main and noun clauses work equally well:
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