this is my first guide.so if i have any mistakes,please inform me.
[size=+2]1.taking down a Gun Turret[/size]

-use tanks(rhino,paladin,challenger and mega tank)
-razorback are useful if the gun turret has a shorter range then it.
-if you still not unlocked any tanks,you may use rocket launcher,flame thrower and suicide bomber,but first send any units and aim the gun turret,then send them in different side.
notes:jackrabbit,rocket buggy and humvees are not recommended because they give less amount of damage on buildings and can easily destroyed by gun turret..
[size=+2]2.taking down a Mortar Tower[/size]

-mortar tower can be easily destroyed in 3 ways:-
a)units that have a high speed(rocket buggy)
rocket buggy can dodge the mortars
b)aircraft
mortar tower cant shoot air units
c)TMT(tanks with medics and techs)
tanks for destroyed the mortar tower,techs for repairing them and medics for healing the techs.lol(send in 2 or more medics so they can healing each other)
notes:the tanks must be in front and followed by the techs and medics(if there are anti infantries in that base)
[size=+2]3.taking down a Bunker[/size]

-tanks are good for taking down a bunker
[size=+2]4.watch out!landmines![/size]

-landmines can damaged all units in a small range but shaped charge gives a high damage
-send 1(the more the better)unit in front and followed by other units behind
EXAMPLE:

[size=+2]5.infantry[/size]
-as in the tutorial you can see a tank in front and some infantries behind.do the same thing.
[size=+2]6.ground units(except humvees)[/size]
-send in some air units because they cant hit them.
-if they are protected by gun turret,first send in some infantries or ground units and run away.while they chasing your units,send some air units to defeat them.
notes:do not send infantries to defeat tanks,except flame thrower and rocket launcher.