After its (1) to the (2) in 2001, China has taken steps towards opening up its (3) . As a condition for joining the WTO, China (4) itself to a (5) of trade liberalization, including the reduction of tariffs on cars and agricultural products. These tariffs reductions are both (6) and there is (7) for China to (8) at a faster pace.
A (9) of (10) and a more rapid and profound reduction of import tariffs would (11) of those Chinese consumers who would (12) imported products at lower prices. Second, a higher (13) into China would take away much upward pressure on the Renminbi and provide a true and lasting (14) to solving current global (15) . Indeed, even a modest (16) in the opening-up process would go a long way towards solving the problem.
The opening up of China’s markets to international competition should (17) deep reforms. Banks should be recapitalized, bad loans provisioned fully and state-owned companies’ runaway indebtedness (18) . Only when real progress in these areas is made should China begin to consider a reform to its (19) . Doing it any earlier would be highly (20) .

把长为3cm的线段AB平移2cm，得到线段A′B′，则四边形ABB′A′的周长是______cm．