Answer:
3.
(i) Open the door.= Imperative sentence.
(ii) How happy we were!= Exclamatory sentence.
4.
(i) What does your father do?= Interrogative sentence.
(ii) May you succeed in life.= Optative sentence.
Explanation:
There are different types of sentences, depending on their form and the implications or purposes. Some of the most common ones are declarative, imperative, exclamatory, or interrogative sentences.
The given sentences are identified as follows-
3. (i) The given sentence is an imperative sentence, for it signals a command. Such sentences either order or asks/make requests.
(ii) The given sentence is an exclamatory sentence that expresses an exclamation. Moreover, it is easily identifiable by the use of the exclamation mark at the end of the sentence.
4. (i) The given sentence is an interrogative sentence as it makes or asks a question, followed by the use of the question mark at the end of the sentence.
(ii) The last sentence is an optative sentence as it expresses a desire, a wish. Such types of sentences either expresses a wish, prayer, or even a curse.