I smoke（嗜好）；I work in London（不变的情况）；London is a large city（真理）
You walk for two hundred meters, then you turn left.
Your exam starts at 09.00.
表达未来的时间，用于特定连接词之后：after, when, before, as soon as, until
He'll give it to you when you come next Saturday.
He drinks tea at breakfast.
She only eats fish.
They watch television regularly.
We catch the bus every morning.
It rains every afternoon in the hot season.
They drive to Monaco every summer.
Water freezes at zero degrees.
The Earth revolves around the Sun.
Her mother is Peruvian.
Open the packet and pour the contents into hot water.
You take the No.6 bus to Watney and then the No.10 to Bedford.
His mother arrives tomorrow.
Our holiday starts on the 26th March
She'll see you before she leaves.
We'll give it to her when she arrives.
构成一般现在时：以 to think 为例
|I think||Do I think?||I do not think|
|You think||Do you think?||You do not think|
|He thinks||Does he think?||He does not think|
|She thinks||Does she think?||She does not think|
|It thinks||Does it think?||It does not think|
|We think||Do we think?||We do not think.|
|They think||Do they think?||They do not think.|
在第三人称单数时，动词一律以 s 结尾：
he wants, she needs, he gives, she thinks.
否定句和疑问句要用 Does（= 助动词 Do 的第三人称动词变化）+ 不带 to 的不定词。
He wants ice cream. Does he want strawberry? He does not want vanilla.
以 y 结尾的动词：第三人称动词要将 y 改为 ies：
fly --> flies, cry --> cries
例外情况：字尾 y 前面有母音：
play --> plays, pray --> prays
当动词原型字尾是 ss、x、sh、ch 时，就在字尾加 es：
he passes, she catches, he fixes, it pushes
- He goes to school every morning.
- She understands English.
- It mixes the sand and the water.
- He tries very hard.
- She enjoys playing the piano.