In the wireless sensor networks, an important issue of area coverage is to know how many sensor nodes are needed in a deployment under a certain kind of distribution. In that way, the nodes can be dense enough to form a complete and connected cover of interest area. Another issue that needs to be addressed is the "redundancy of connectivity" caused by the use of the well known sufficient condition that "the communication range is at least twice the sensing range". In this paper, we show our result in solving these problems, a practical method to form a connected -coverage with a connected dominating set (CDS). By introducing a measure of node density called the biggest vacant square territory (BVST), we prove that the point coverage offered by a CDS implies area coverage of the area of interest. The 1-point-coverage of a CDS with a reduced R and a certain number of deploying sensors guarantees -area-coverage, or simply -coverage. Such assurance is verified via a simulation study on the CDS in [7] under random node distribution.