什麽400次？
不過根據科學來說，the production of sperms should be 300 million per day, and the normal sperm production should be 100 million/ml. If a man produces less than 20 million/ml, it is considered to be sterile, which means he cannot make a woman pregnant. 由此看來可能不是次數多少，應該是ejaculate 多少。
隨便聊聊，正好用到考試內容。 嗬嗬。
