Question

1. He said that in normal times, laboratories can find out if you have the common cold.

2. He said that in normal times, laboratories could find out if you have the common cold.
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Do we have to use 'can' or 'could' in the subordinate clause? In the main clause, the tense is the past(said).

Answer 1

1. He said that in normal times, laboratories can find out if you have the common cold.

2. He said that in normal times, laboratories could find out if you had the common cold.
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Do we have to use 'can' or 'could' in the subordinate clause? Do we have to use 'have' or had'? In the main clause, the tense is the past(said).Thanks for your help.

Answer 2

Both sentences are correct, depending on whether “you” are sick now (#1) or are not sick anymore (#2).