The problem is you forgot the closing bracket when creating dy1.
[T,Y] = ode45(@Bqfun1,[0 2],[1 1 -0.01]);
plot (T,Y(:,1),'b','linewidth',1)
function dy1 = Bqfun1(t,y)
dy1 = zeros(2,1);
dy1=[y(2)
y(3)
-3*y(3)-3*y(2)-y(1)-4*sin(t)];
end