Exercise 3: Read the text below and choose the correct word for each space. For each question, circle the correct letter A, B, C or D. LOUIS BRAILLE (1809 – 1852) Louis Braille (0) was_ the son of a French leather worker. He (1) ___________ blind at the age of three when he fell on a tool in his father’s workshop. But Louis was a (2)____________ and talented boy. He (3) _________ to be a musician, so he learned to play the cello, and at the age of ten he (4)_____________ a scholarship to The National Institute for Blind Children in Paris. He could play the cello, (5)_____________ he (6) ________ read or write. In 1819 a French soldier, Charles Barbier, (7)____________ “night writing”. He used patterns of twelve raised dots on paper so that soldiers could read (8) ____________ dark. Louis Braille understood the importance of this invention for blind people and (9)___________ he was fifteen, he began to develop it. He made it simpler with six dots, not twelve. In 1829, he (10)___________ it at the Institute. 0. A. was B. had C. did D. made 1. A. came B. went C. reached D. got 2. A. brave B. courage C. able D. possible 3. A. passed B. considered C. wanted D. promised 4. A. defeated B. beat C. became D. won 5. A. so B. and C. but D. however 6. A. couldn’t B. wouldn’t C. mustn’t D. can’t 7. A. invented B. discovered C. found out D. set up 8. A. under B. at C. with D. of 9. A. then B. while C. at D. when 10. A. introduce B. introduced C. introduces D. was introducing

Câu 3: Cho hình chóp S.ABCD, trong đó ABCD là một hình thang với đáy lớn AD. Gọi H và K lần lượt là trung điểm của AB và DC. Gọi G là trọng tâm của tam giác SAD. Giao tuyến (d) của hai mặt phẳng (SAD) và (GHK). Biết (d) cắt SA tại M và cất SD tại N. Tứ giác MNKH là hình bình hành thì AD =k.BC. Khi đó k =?