$$PC{l_3}$$   reacts with water to form

Solution :
$$PC{l_3}$$  is easily hydrolysed by water to give $$POC{l_3}$$  and finally it gives $${H_3}P{O_3}$$  and $$HCl.$$
$$PC{l_3} + {H_2}O \to POC{l_3} + 2HCl$$
$$POC{l_3} + 3{H_2}O \to {H_3}P{O_3} + 3HCl$$