add to

add, add to, add...to, add up to

都是add的固定搭配词组。
add: 作“加，增加”解时，既可作及物动词，又可用作不及物动词；作“又说，补充说”解时，与直接或间接引语连用。

• if the tea is too strong, add some more hot water.
  如果茶太浓了，再加点开水。
• after a short while, he added that he would try his best.
  过了一会儿，他又接着说他会尽力。

add to: 意为“增添，增加，增进”。

• the bad weather added to our difficulties．
  恶劣的天气增加了我们的困难。

add...to: 意为“把......加到......”，是把前一项加到后一项之后或之中。

• add two to seven, and you will get nine.
  七加二等于九。

add up to: 意为“加起来总共是／累计得”，该短语不用于被动语态。

• all his school education added up to no more than one year.
  他的学校教育加起来不过一年。

动词 add to:

1. have an increased effect

1. I have nothing to add to my earlier statement.
   我对我先前说的话，没有什么补充的。
2. Being still hale and hearty in spite of his seventy years, my father was able to add to his pension by selling vegetables from his garden.
   我的父亲尽管70高龄，身体仍很硬朗，还能把菜园子里的菜挑出去卖，以挣些零化钱。
3. I didn't want to add to Mother's misery.
   我不愿意增加母亲的痛苦。
4. The function of an adjective is to describe or add to the meaning of a noun.
   形容词的作用是描述或增加名词的意思。