46. Bell experimented with ways of transmitting..................over a long distance. SPEAK 47. It is ........................... to eat too much sugar and fat. HEALTH 48. After having taken an aspirin, her headache........................ APPEAR 49. Our main............................... to export are rice, coffee and rubber. PRODUCE 50. This form must have the............................. of the writer. SIGN Giusp mik với ạ! Giải thích nx ạ!!!

46. Bell experimented with ways of transmitting..................over a long distance. SPEAK  

=> Bell experimented with ways of transmiting speech over a long distance. (SPEAK)

Sau of+N => speak-> speech

47. It is .........healthy.................. to eat too much sugar and fat.    HEALTH  

It is +adj+to...: nó như thế nào để

=> health-> healthy
48. After having taken an aspirin, her headache........................   APPEAR  

Sau khi uống thuốc giảm đau, cơn đau đầu của anh ấy biến mất

=> appear-> disappear

49. Our main............................... to export are rice, coffee and rubber.  PRODUCE 

sản phẩm chính để xuất khẩu=> product

Căn cứ vào từ "are" => products
50. This form must have the............................. of the writer.    SIGN 

the+N => signature(chữ ký)