S11 I can subtract TU - TU with exchanging.



S12 I can subtract HTU - TU with exchanging.

S13 I can subtract numbers involving negative numbers set out on a number line.



S14 I can subtract HTU - HTU with exchanging.

S15 I can subtract and p.



S16 I can subtract ThHTU HTU.

S17 I can subtract U.t U.t.