How do you plan to solve it?
module t_ff_async_pr ( input CLK, input RST, input PRE, input T, output reg Q ); // Write your code here always@(posedge CLK or posedge PRE or posedge RST) begin if(RST) Q<=0; else if(PRE) Q<=1; else if(T) Q<=~Q; else Q<=Q; end endmodule