was or were?
Between the moment when Crooks and Lennie (was/were) in his room..
Crooks and Lennie are plural so the verb is WAS.
Also, what can I substitute for affect?
It will affect his future.
The verb should be "were" (plural form).
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To determine whether to use "was" or "were" in the given sentence, you need to consider the subject and the verb form for subject-verb agreement.
In this case, the subject is "Crooks and Lennie" which is a compound subject. When you have a compound subject joined by "and," you usually use the plural form of the verb. Therefore, the correct verb form to use is "were."
The correct sentence would be: "Between the moment when Crooks and Lennie were in his room..."