有许多种氨基酸人体自身不能合成.There are many amino acids that the body cannot synthesise itself.有许多种氨基酸人体自身不能合成。There are many amino acids that the body cannot synthesize itself.丙氨酸在转氨作用中似乎是更好的氨基酸.Alanine appears to be the preferred a...
在温暖的环境中，咳嗽和喷嚏传播疾病的速度要快得多。Coughs and sneezes spread infections much faster in a warm atmos-phere.门边的那些人马上同时打起喷嚏来.The people near the door began sneezing all at once.感冒时, 要打很多喷嚏.When you have a cold, you sneeze a lot....