Your question is incomplete because it does not provide the options or the underlined verb. The complete question is the following:
Akira sewed one button back on his jacket. Then, another one <u>falls</u> off when he put it on to go outside.
will fall
has fallen
fell
had fallen
Answer:
fell
Explanation:
The sentences describe a series of events that occurred one after the other in the past, so the correct tense is Past Simple. Actually, the second sentence begins with the word <em>then</em>, which indicates a sequence of actions that happened after Akira sewed the button. Thus, one of the uses of Past Simple is to illustrate an arrangement of complete actions that happen in chronological order in the past.
The rest of the choices are incorrect because <em>will fall</em> refers to the future, <em>has fallen</em> connects past and present, and <em>had fallen</em> specifies an action that occurred before another past action.
