Sounds like and Sounds as if means "I think I hear",
Looks like and Looks as if means "I think I see"
(Use Like when you are sure, use As if when you are not very sure.)
Examples of I think I hear:
"Tom! It sounds like someone just shot a gun!"
<I think I hear the sounds of a gun.>
<Sound of rain, of lightening, of thunder>
"David, I do not see any clouds, but it sounds as if it is raining!"
<I think I hear the sounds of rain, but I am not sure it is raining.>
Examples of I think I see:
<You see smoke coming out of a house>
"Tom! It looks like a fire!"
<I think I see a fire>
<You meet a friend who was sick, but now, is at school again>
"David, it looks as if you are feeling better today!"
<You think your friend looks better is better today, but you are not sure>
Sounds like, Looks like, and Seems like can ALSO be used to say,
"I think I understand that..." or "I believe..."
Examples of I think I understand or I believe...
Me: "Ohhhh... I am so tired, my job was bad, my friends were mean, I hate my job."
You: "Mmmmm... it sounds like you had a bad day."
<I think I understand, I believe that you had a bad day."
Me: "I love my new wife, she is very pretty, and she loves me."
You: "It looks like you married a wonderful woman!"
<I believe or I think I understand that your wife is wonderful>
Me: "I do well in school, and my boss pays me more money now!"
You: "It seems like your life is very happy now."
<I believe or I think I understand your life is good>
And again, you can us the AS IF form if you are NOT SURE or DO NOT REALLY BELIEVE what you are saying.
"My friend David says he is very happy, his wife loves him, and he has a lot of money. It seems as if his life is perfect. BUT.... I know that he is very sick, and will die soon. It seems as if everything is good for him, but the truth is, his life is bad."