Selecting same attributes as of training set on test set

Nona

hi All,
I am working on a dataset with large number of attributes. I am doing some feature selection before training the model. My problem is that when i select some features and train the training set, how can i choose same features from the test set before applying the learnt model on that. There are some operators like select by weights that return weight as well as the examples; i can use same weights on the test set to select same features as were there for training set but some feature selection operators just return the example set to work on and nothing else..then in that case how can i select the same set of features that were chosen for training set by such operators.  ???
Thanks