$(CH_3)_3 \, \overline C , \overline C Cl_3 ,(CH_3 )_2 \overline C H ,C_6 H_5 \overline C H_2$
(1) $CH_2=CH_2$
(2) $[Figure]$
(3) $H-C \equiv C-H$
(4) $NH_3$