SHANGHAI A shares provided the main action on the China exchanges last week, finishing sharply higher after a week-long dive. Shenzhen remained dull for most of the week as investors backed off, a little wary after the B share market shifted to US dollar denominations on Monday. Shenzhen A shares dropped back to close the week down 1.2 per cent at 2,861.37 after a technical rebound on Thursday had added 6.7 per cent. The Credit Lyonnais Shanghai A Index put on 10.29 per cent to finish at 6,850.59 in active trading, almost making up for the losses earlier in the week. Investors seemed to be buoyed by the belief that the market had reached bottom. The market had been confused about various bonus issues and corporate earnings that were below rosy market projections. Shenzhen B shares ended the week on a quiet note, with light trading in only two of the nine issues. The Credit Lyonnais Index closed down 0.49 per cent at 1,326.97. Shanghai B shares were given a lift by the stalwart performance of the A shares. Prices advanced 4.4 per cent on the back of Thursday's 2.4 per cent leap. The Credit Lyonnais Shanghai B Index closed at 997.89.