Choose the correct answer to each of the following questions.

Câu hỏi

When the boss walked into the office, his secretary ________ a letter.

A. has been typing

B. was typing

C. is typing

D. had typed

Đáp án
B. was typing

Câu hỏi thuộc Bài tập:

MỤC TIÊU 5+ CHO ĐỀ THI GIỮA KÌ 1 (23-24)(NGỮ PHÁP-HÌNH THỨC TỪ-SỬA LỖI SAI)