Wah How to use "as if / like"

We can use as if / like as conjunctions to make comparisons.

    (1.) Jason talks as if he knew everything. 
    (2.) Jason talks like he knows everything.

Sentences (1.) and (2.) have the same meaning, but sentence (1.) is more formal. 
As you can see, as if is followed by the past tense, but like is followed by present tense.
In both (1.) and (2.) sentences are used to describe the unreal situation.  
( because Jason never ever knows everything in this world. )

    (3.) James acts as if he were a child. (He is 30 years old, he is not really a child.)

When we talk about the unreal situation. We usually use were instead of was even when the subject is I,he,she,it. ( like in these topics:
Wah How to use If I were you,...
Wah How to use second conditional. )

Look at next sentences:

    (4.) Jennifer seems as if she is tired. (Maybe she is tired, but maybe she is not.)
    (5.) Jennifer seems like she is tired.

We will see as if in sentence (4.) is followed by the present tense because we are not sure whether it's real or not. 
And again like in sentence (5.) is still followed by the present tense.

Note: Like forms are followed by the present tense in both the unreal and real situations.

• She gives everyone orders as if she owned this company.
• That man bows to me as if he knew me.
• Why do you talk about him as if he were an old man?
• They stared at me as if I were crazy.
• Hey!, don't act as if I were a baby.
• Scarlett walks as if she were a supermodel.

She spends money as if she owned a bank.