1.if my brother (to be) in trouble, i shall help him

1. If my brother is in trouble, I shall help him, of course. This is First  Conditional, it means that the condition, expressed in the if-clause, is rather probable and often refers to the future. However, remember non to use any future tenses after the conjunction if in the if- clause, use only Present tenses. Some examples: If I happen to see Helen, Ill certainly tell her to call you immediately. If she is failing at the entrance exams, she will start working somewhere. If she passes her driving text, her husband will buy her a new car.