be left high and dry(be isolated and without help;as a hog on ice)

each has a role to play(all be properly placed and provided for)

A single palm can not clap; It's hard to succeed without support.

look on at sb's trouble with indifference

as liked closely as flesh and blood

frank and forthright

Each sticks to his own view.

change only the appearance

strut about(as hold as brass; gallop and triumph)

Once the key linkis grasped; everything else falls into place.

overcome all the difficulties on the way

strongly fortified

Each has its own merits.

show the deepest sincerity

be quite content even in adversity

fail to succeed for lack of a final effort

break one's heart(be heartbroken as the liver and bowels have been cut to pieces)

Let each speak mind

deeply rooted and firmly planted; have a firm foundation

birth of a new baby(first see the light)