Condense the loganithmic.
\[
\log y+4 \log z=
\]

Step 1 ：The given expression is a sum of logarithms. According to the properties of logarithms, the sum of logarithms is equivalent to the logarithm of the product of the numbers. Specifically, the property is \(\log_b(m) + \log_b(n) = \log_b(mn)\).

Step 2 ：In this case, we have \(\log y + 4 \log z\). The 4 in front of the \(\log z\) can be moved to the exponent of z, according to the property \(a \log_b(c) = \log_b(c^a)\).

Step 3 ：So, the expression can be rewritten as \(\log y + \log z^4\), which can then be combined into a single logarithm as \(\log (yz^4)\).

Step 4 ：Final Answer: \(\boxed{\log (yz^4)}\)