You can tell it's silk by the feel. 你摸摸就知道是绸缎。
fine vt. 罚款
He was fined for speeding. 他因超速驾驶被罚款。
finger n. 手指
There are five fingers on each hand. 每只手有五个手指。
flight n. 飞机的航程；飞行，飞跃；班机
f light（轻的）→飞行
The flight will take four hours. 这次航行要飞4个小时。
The flight takes approximately three hours. 飞行时间大约需要三小时。
form v. 形成
Steam forms when water boils. 水煮沸之后就形成蒸汽。
