SENTENCE

a. It has a subject (noun) and a predicate (what the subject has or does).

b. The sentence must make sense.

c. Start with a capital letter.

d. End with a full stop (.) or other punctuation marks such as question mark (?) or exclamation mark (!).

For example:

a. Use a full stop (.) at the end of a declarative sentence.

For example:

- Tomorrow early morning first I go to morning walk. <-- (full stop)

- I and my sister don't see each other anymore. <-- (full stop)

- George brushes his teeth twice a day. <-- (full stop)

b. Do not use a question mark (?). 

For example:

- Tomorrow early morning first I go to morning walk? <-- (wrong)

- I and my sister don't see each other anymore? <-- (wrong)

- George brushes his teeth twice a day? <-- (wrong)

c. Do not use an exclamation mark (!). 

For example:

- Tomorrow early morning first I go to morning walk! <-- (wrong)

- I and my sister don't see each other anymore! <-- (wrong)

- George brushes his teeth twice a day! <-- (wrong)