无法将类型“System.Threading.Tasks.Task<string>”隐式转换为“string”

private Task<string> methodAsync() {
    Thread.Sleep(10000);
    return "Hello"; //Error: Cannot implicitly convert type 'string' to 'System.Threading.Tasks.Task<string>'
}
private async void button1_Click(object sender, EventArgs e)
{
    string s = await methodAsync();
    MessageBox.Show(s);
}
修改

private async void button1_Click(object sender, EventArgs e)
{
    var s = await methodAsync();
    MessageBox.Show(s.Result);
}