there, but for the grace of God …

They're, there and their all sound the same; hence the problems.

they're

We saw that an apostrophe can stand for a missing letter and that's what we have here.

they're = they are

So if they are can be substituted in your sentence it's they're

they're late = they are late

there 

refers to a place. Think of here and there

It also is used for 

There is / There are / Isn't there? / Aren't there? /There was / There will be, etc

If you can substitute here in your sentence without it sounding too much different, then use there.

There is a fly in my soup. (Here is a fly in my soup.)

their

is the possessive form of they, meaning belonging to them, of them

Their house was burgled.

Test yourself:

1. … going to the cinema.
2. It was … I met my wife.
3. … are many things to remember, aren't …?
4. They lost … luggage …
5. If … all coming we need more chairs.

Answers: paste the upside down answers into FLIP

 to save turning the computer upside down!

˙sɹıɐɥɔ ǝɹoɯ pǝǝu ǝʍ ƃuıɯoɔ llɐ ǝɹ,ʎǝɥʇ ɟı ˙5  
˙ǝɹǝɥʇ ǝƃɐƃƃnl ɹıǝɥʇ ʇsol ʎǝɥʇ ˙4  
¿ǝɹǝɥʇ ʇ,uǝɹɐ 'ɹǝqɯǝɯǝɹ oʇ sƃuıɥʇ ʎuɐɯ ǝɹɐ ǝɹǝɥʇ ˙3  
˙ǝɟıʍ ʎɯ ʇǝɯ ı ǝɹǝɥʇ sɐʍ ʇı ˙2  
˙ɐɯǝuıɔ ǝɥʇ oʇ ƃuıoƃ ǝɹ,ʎǝɥʇ ˙1   

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