box practice questions

en/src/smart-pointers/box.md

@@ -1 +1,41 @@
 # Box
+
+1. 🌟
+```rust,editable
+// Make it work
+fn main() {
+    let b = Box::new(5);
+    assert_eq!(*b, 5);
+
+    println!("Success!");
+}
+```
+
+2. 🌟
+```rust,editable
+
+// Make it work
+fn main() {
+    let b = Box::new("Hello");
+    print_boxed_string(b);
+}
+
+fn print_boxed_string(b : Box<&str>) {
+    println!("{}", b);
+}
+```
+
+3. 🌟
+```rust,editable
+
+// Make it work
+fn main() {
+    let b1 = Box::new(5);
+    let b2 = b1;
+    assert_eq!(*b2, 5);
+
+    println!("Success!");
+}
+```
+
+> You can find the solutions [here](https://github.com/sunface/rust-by-practice)(under the solutions path), but only use it when you need it