NatScience 5: 3

Something that is very difficult to break , for example , metal , is something ____________________ .
Something that you can bend , for example , a rope , is something ____________________ .
Something that is very pleasant to touch , for example , fabric , is something ____________________ .
Something that you can't see through , for example , a wall , is something ____________________ .
Something that you can't bend , for example , a rock , is something ____________________ .
Something that you can see through , for example , a window , is something ____________________ .