how long意为“多久、多长时间”,主要是对一段时间进行提问,答语通常是（for）three days/weeks/months等时间段,它可用于各种时态.
how soon意为“还要多久”,是对从某个基本时间到将来某动作结束或某动作发生这段时间提问,常用在一般将来时态的句子中,其答语通常是“in + 一段时间”.
how often意为“多久……次、是否经常”,用来提问在某一特定的时间进行某个动作的次数,答语通常是always,usually,often,sometimes,once/twice a day/month等.
be made of,be made from,be made in,
be made of,be made from,be made in,
be made by,be made for,be made out of
be made of和be made from都表示“由……制成”,主语为制成品.
1.be made of 表示制成成品后,仍可看出原材料是什么,保留原材料的质和形状,制作过程仅发生物理变化.如：
The kite is made of paper．风筝是用纸做的.
2.be made from 表示制成的东西完全失去了原材料的外形或特征,或原材料在制作过程中发生化学变化,在成品中已无法辨认.如：
The paper is made from wood．纸是木头做的.
Butter is made from milk．黄油是从牛奶中提炼出来的.
3.be made in表示某物在某地生产或制造,in后接表示地点的名词.如：
This TV set is made in Shanghai．这台电视是上海制造的.
4.be made by表示“由（谁）制造”,by后接动作的执行者.如：
The machine is made by the workers in the factory．这机器是由工厂里的工人们制造的.
5.be made for表示“为……而制造”.如：
These desks were made for the students．这些书桌是为学生们做的.
6.be made out of是指从什么东西被改造成另一种东西.如：
The fences are made out of soda cans.