DOC fix typos in cross validation user guide
@@ -323,11 +323,11 @@ The following cross-validators can be used in such cases.
While i.i.d. data is a common assumption in machine learning theory, it rarely
holds in practice. If one knows that the samples have been generated using a
-time-dependent process, it's safer to
-use a :ref:`time-series aware cross-validation scheme <timeseries_cv>`
-Similarly if we know that the generative process has a group structure
-(samples from collected from different subjects, experiments, measurement
-devices) it safer to use :ref:`group-wise cross-validation <group_cv>`.
+time-dependent process, it is safer to
+use a :ref:`time-series aware cross-validation scheme <timeseries_cv>`.
+Similarly, if we know that the generative process has a group structure
+(samples collected from different subjects, experiments, measurement
+devices), it is safer to use :ref:`group-wise cross-validation <group_cv>`.
K-fold
