The counter that doesn't look: 个

Where the picture shows up in 个

1. 1

   just one of them

   我要一个。

   wǒ yào yí ge

   I'll take one.

2. 2

   people are lumps too

   我们组有五个人。

   wǒmen zǔ yǒu wǔ ge rén

   There are five of us on the team.

   For 'two' use 两, not 二: 两个人.

3. 3

   the one at your fingertip

   这个多少钱？

   zhège duōshao qián

   How much is this one?

4. 4

   even what you can't touch

   我有一个问题。

   wǒ yǒu yí ge wèntí

   I have a question.

5. 5

   even an hour is one lump

   请等一个小时。

   qǐng děng yí ge xiǎoshí

   Please wait an hour.