IT --- --- NOT UNTIL THEY HAD TO FIND A JOB THAT THEY LEARNED ENGL...

20. It --- --- not until they had to find a job that they learned English.

a. were

b. was

c. is

d. are

* Khoanh tròn từ hoặc cụm từ ( a,b, c, hoac d) để điền vào chỗ trống: