What are the examples from now on?

1, the subject is expressed by the present tense. If the main clause uses the future tense, the clause uses the present tense.

If it doesn't rain tomorrow, I will go to school on foot.

The main sentence is "I will walk to school" with "will", which means that in the future, if there is "am/is/are going to" in the sentence, it is also the general future tense, not rain is a clause, and "does t" in the sentence well reflects that it is the general future tense, while tomorrow is an adverbial of time, usually represented by "if".

2. If the sentence is imperative, the main imperative sentence should be the simple present tense.

Please let me know if he comes back.

This is the main prayer from now on. The main sentence is please let me know, and "please" is an imperative sentence. Imperative sentences usually begin with do. At the beginning, let, no, never, do, "he is back" is a clause, and "coming" means ordinary present. ?

3. Subjective emotion from the present should mean that if there is a modal verb in the sentence, then the modal verb is followed by the verb of the ordinary present tense, that is, the verb prototype.

If you feel hungry, you should eat something.

This is a subjective feeling. "You should eat something" is the main sentence, "should" is a modal verb in the sentence. The commonly used modal verbs are can, may, must and should, and "you feel hungry" is a clause.

Summary: It mainly depends on whether there are words such as if, when and as soon as possible ..... Sometimes it means that the master comes from the present, the master prays from the present, and the master feels from the present. Note that "when" can sometimes be used with continuous verbs or instantaneous verbs.