问题
选择题
No sooner had he got home than he ____his coat and sat down at the table.
A．threw off
B．threw out
C．threw about
D．threw sway
答案
A
throw off意为“匆匆脱掉(衣物)，扔掉，摆脱掉”，throw out为“(尤指无意间)吐露，说出”，throw about为“乱扔”，throw away意为“扔掉，抛弃”。
)，产生磷核(
)和x粒子，磷核(
)和y粒子，则x粒子和y粒子分别是