The sky appears clear.
The sky is clear and sunny
The sky appearing clear doesn't necessarily mean it is sunny.
exists e1 p1 x1.(n_sky(x1) & exists s1.(Theme(s1,x1) & a_clear(s1)) & Topic(e1,p1) & Actor(e1,x1) & v_appear(e1))
exists s1 s2 x1.(n_sky(x1) & Theme(s2,x1) & a_sunny(s2) & Theme(s1,x1) & a_clear(s1))