Choose the best answer for the following sentence:
It is said that reading ______________ of a child when he leams to evaluate information in the book. 
A. sharpen the thinking processes
B. weaken the thinking processes
C. sharpens the thought processes
D. weakens the thought processes

Choose the best answer for the following sentence:
The country experienced prosperity during the Kennedy _____________. 
A. administer              
B. administration                
C. administrative                  
D. administrator

Choose the best answer for the following sentence:
If he hadn’t wasted too much time, he ___________ in his examination. 
A. would fail               
B. wouldn’t fail
C. wouldn’t have failed                
D. won’t fail

Choose the best answer for the following sentence:
He congratulated me __________ winning the competition. 
A. of                 
B. on                 
C. at                 
D. about

 Hàm số $y=\sin 2x$ tuần hoàn với chu kì
A. $T=2\pi .$
B. $T=\pi .$
C. $T=\frac{\pi }{2}.$
D. $T=\frac{\pi }{4}.$

Choose the best answer for the following sentence:
I ______________ to New York three times this year. 
A. have been             
B. was                 
C. were                
D. had been

Choose the best answer for the following sentence:
He got such a fright. He was _____________ frightened. 
A. so                 
B. such                 
C. such a                    
D. a so

Phương trình $\sin x+\sin 2x+\sin 3x=\cos x+\cos 2x+\cos 3x$ có tập nghiệm trùng với tập nghiệm của phương trình nào sau đây?
A. $\sin x=-\frac{\sqrt{3}}{2}$ 
B. $\cos 2x=\sin 2x$ 
C. $\cos x=\frac{1}{2}$ 
D. $\left[ \begin{array}{l}\cos x=-\frac{1}{2}\\\cos 2x=\sin 2x\end{array} \right.$

 Trong các hàm số sau, hàm số chẵn là
A. $y=-\sin x.$
B. $y=\cos x-\sin x.$
C. $y=\sin x.cosx.$
D. $y=\cos x+{{\sin }^{2}}x.$

Phương trình $\frac{\sin 2x}{\tan x-1}=0$ có nghiệm là
A. $x=k\frac{\pi }{2},k\in Z.$
B. $x=k\pi ,k\in Z.$
C. $x=\frac{\pi }{3}+k2\pi ,k\in Z.$
D. Vô nghiệm.