Here are 2 sentence first is "We will not leave tomorrow" and second is "They will be late for work". we have used "be" in the second sentence but not in first sentence.Why? Please ! answer the given question....

Here are 2 sentence first is "We will not leave tomorrow" and second is "They will be late for work". we have used "be" in the second sentence but not in first sentence.Why? Please ! answer the given question....

generally we use main verb form with will. Here in the first sentence leave is a verb whereas in the second sentence "to be late" is the main verb.