Đáp án + Giải thích bước giải:

Justin: Hold on. Okay, I (check) am checking the oil right now. It (look) looks clean, and the tank is full.

I just filled it up last week, so I didnt think that would be the problem.

Beto: Okay, thats good. Now you need to test the battery. (You, have) Do you have a battery tester?

Justin: Yes, I do. My brother got me one for my birthday. Lets see...okay, I (use) am using it right now.

The battery (appear) appears to be full of life.

Beto: Hmm. That is strange.I (wonder) wonder what the problem could be!

Justin: Yes...very strange. I (not, understand) do not understand it. My brother thinks the motorcycle is

trash. He (not, think) does not think it will ever start again. He (say) says I need to take it to the junkyard.

Beto: Thats too bad. Well, there (be) is one more thing you can check.

Justin: Really?

Beto: Yes, but I am sure you (check) have checked it already. Its probably the first thing you thought of.

Justin: Well, what is it?

Beto: The gas level.

Justin: Wait! I (not, check) have not check that yet! Hold on! I (check) am checking the gas level now.

Beto: Well, what (do) does it look like?

Justin: It (look) looks empty! Wow, that (be) is the problem. How embarrassing I am sorry that I bothered you about this!

Beto: Thats okay. The same thing (happen) has happened to me before. You had better go get some gas! Talk you to you later!

Justin: Okay, thanks!

______________________________________

`-` Thì HTĐ:

(`+`) S + Vs/es 

(`-`) S + do/does + not + V(nguyên mẫu)

(`?`) Do/Does + S + V(nguyên mẫu)

`-` Thì HTTD:

(`+`) S + be + V-ing

(`-`) S + be + not + V(nguyên mẫu)

(`?`) Be + S + V(nguyên mẫu)

`->` Dấu hiệu: now

`-` Thì HTHT:

(`+`) S + have/has + V3/ed

(`-`) S + have/has + not + V(nguyên mẫu)

(`?`) Have/Has + S + V(nguyên mẫu)

`->` Dấu hiệu: yet, already