for me，it is familiar。although i used it many times，i want know it's mean。mean is not small，but is big too。realizement is long procedure，need patience for comprehend。each mean is a segment story，not the words and talks。after realised impression could deep ，analyze can urge development。it will produce surprised worth when you trust enough it。in fact，i can't use it absolutely according mean。sometimes，mean became a kind of symbo。of course，i ever change this situation，but conclusion was not obvious。

if means assume、guess and a kind of analyzement。the conclusion usually in back of sentence of if lead。if always in front，not in back。the sentence of if lead is not such important，even no worth to talk it is light or heavy。it is so untalkble，why did user use it ？we know there is no if，does if sentence has reason to exist？question did not solve down，back and became more。i guess if sentence is flower in bottle ，only for look。maybe if sentence has some important effect，but i don't know。

many times，word not only word。if sentence mean not real ，though is emphasizing something。for user，if sentence just is a kind of expression。beside symbol，nothing is remained。

if something is that，so it must be that。cause sure，so judge。because of enbelieve，course has bomboo in heart(mean someone has confidence)。first step，select。second step，decide。it seems like a question，factly is plenty troubles。it is easy to say a sentence，it is difficult let sentence conform fact。if is a startance，absolutely not endment。someone said if represents hope and wishment。the other said if is a kind of linguistic power。only need you have no doubt，it just is of nail nail in board。

in fact，i always use it。it enlightened me a lot。in future，i may renew write if。