When do we use BY with the future perfect tense?

Answer 1

In English, the word "by" is often used with a future tense to show a specific point or time in the future. Similar to giving a deadline, or a due date of when something has to be done.

3 Examples of a deadline (or due date)

1. By + Specific Time in the future: "I will finish my homework by 5 PM tomorrow."
2. By + a Time Frame in the future: "They will finish building the house by the summer."
3. By + a Deadline in the future: "Please submit your application by September 1st."

Remember clocks, calendars, and seasons, all indicate time. For example, by 7 am, by March 3, by Winter, by tomorrow afternoon.

Answer 2

"By" explains the method, time, or place of something..

Some examples are below.

We will have danced by the moonlight.

We will have walked by Mr. Johnson's house when we get home.

I will have cleaned my room by the time my parents come home.

She will have worked hard by using her computers.